LCGB Forums

excellent article about adjustable timing this month.
i once thought about rigging up an adjusable stator plate on a worm drive to adjust from a lever on the bars but never got around to trying it out.
looks like there is selectable timing and even fuel injection coming along soon... who'd have thought it eh !

Can't believe that nobody seems to have tested the best advance at every 500 rpm and drawn up a scale sometime.

Yep, I've just read mine too and thought it was a good insight into the workings of advance/retard. What I particularly liked was the point being made about dynos being a wonderful tool but that real world road testing can show things in a very different light.

Well done Martin.

Adam

So let me put this into perspective. A paying punter pays his money to a very respected and trustworthy dyno operator who does a complete quality set up and run and finite adjustments to obtain optimum performance delivery with a print out of bhp/torque etc. Then the scooterist has to play with the timing and fuelling to get it to run right ?
I have no idea how much it costs to dyno but we do see a good number of scooterists on the forums who once out on the road need to make further alterations.
In the article in Jetest, this is precisely what happened. So my point is; what's the point?
Blue touch paper lit and standing back !

thats about the size of it Chris but I doubt any dyno tech would claim that once set up it didn't need final tuning on the road especially after being run in.

I think dyno tuning is all very well if you want to get every last vestige of power out of an engine and see the results of your tuning in real time on a screen .
or you haven't a clue how to go about jetting, setting up timing and tuning yourself. It will also throw up any equipment faults and combination problems you might be completely unaware of but for me I'd prefer to do it myself on the road .

Ears eyes nose and intuition !

CHRIS in MARGATE wrote:Ears eyes nose and intuition !

Ears, eyes, nose , intuition & cussing Chris .... lots of cussing

CHRIS in MARGATE wrote:So let me put this into perspective. A paying punter pays his money to a very respected and trustworthy dyno operator who does a complete quality set up and run and finite adjustments to obtain optimum performance delivery with a print out of bhp/torque etc. Then the scooterist has to play with the timing and fuelling to get it to run right ?

Hang on a moment Chris: the back story needs a bit of explanation.

SIP kindly supplied the HHP CDI but because of other commitments, I didn't have time to fit the CDI and test it. I was fast running out of time before I needed get the article to Linda, so I asked John at Jahspeed if we could do some dyno runs first thing on a Saturday morning (his busiest day). I was there with John at 7:30, but due to local restrictions, we couldn't do the runs until 9am, when proper customers were starting to arrive.

All I wanted John to do was 4 runs, one on each setting. I didn't ask him to fine tune the carburation or set the bike up. In the end, we did two sets of 4 runs and I included this in the article because they gave a different perspective to the story. As John was offering his services to me (and therefore to the LCGB) without charge, I did not think it appropriate ask for anything more than I considered sufficient to complete the article.

John will happily tell you that the dyno is just a great big tool in his tool box, and like all tools, it is used as and when required. It can tell you lots of useful data, but ultimately, we all rely on how an engine feels when it is on the road.

So please don't think that John failed to set up the machine, because this was not what I asked him to do. If he had of got is spot-on, what would I write about next edition?

I hope this clarifies the matter.

The graph in the article is a bit small so here it is again for those who don't wish to use a massive magnifying glass.



As you can see, there is still some work to be done.

I wasn't having a dig at you or this highly respected dyno operator.
Your article said you ride down with the unit in position 3 and it was fine with no pinking .At the shop you retarded the stator plate further back and in position 3 on the way home it pinked. That was a condition not highlighted by a dyno but by your own ears and intuition. That was all mate.

Thanks for the reply Chris.

Understood.

The ultimate would be programable ecu with lamda sensor, crank position sensor, engine temp sensor and throttle body/fuel injection with maf sensor. Engine life would be greatly improved..